OBJECTIVE:: To determine whether cochlear hydrops analysis masking procedure (CHAMP) has diagnostic value in patients with definite Ménière's disease (MD) comparing the diagnostic validity index of CHAMP with those of electrocochleography (ECoG). STUDY DESIGN:: A prospective study. SETTING:: Tertiary referral center. PATIENTS:: One hundred eight patients were classified into 3 groups: the "definite MD" group (MD group, n = 47); the "non-MD" group (n = 41) of other vestibular diseases including vestibular neuritis, and benign paroxysmal positional vertigo; and the control group (n = 20), which included patients without dizziness. INTERVENTIONS:: CHAMP and extratympanic ECoG were performed in all patients. MAIN OUTCOME MEASURE:: Sensitivity, specificity, and definitions of abnormal values were less than 0.3 ms in latency delay (0.5 kHz high pass noise [HPN]-click alone) and less than 0.95 in compound amplitude ratio (click alone-0.5 kHz HPN/click alone) in CHAMP and 0.4 for the summating potential/action potential ratio in ECoG. RESULTS:: The mean latency delay and amplitude ratio of CHAMP in the MD group significantly differed from these values for other groups, whereas the mean summating potential/action potential ratio of ECoG did not. In ECoG, sensitivity was as low as 21%, specificity was 97%, and diagnostic accuracy was 62%. Sensitivity, specificity, and diagnostic accuracy of CHAMP were 64%, 98%, and 80%, respectively, in latency delay and 91%, 83%, and 88%, respectively, in amplitude ratio. The sensitivity and diagnostic accuracy of CHAMP were significantly higher than the corresponding values for ECoG. CONCLUSION:: CHAMP is more valuable in detection of definite MD than extratympanic ECoG.